[mob][photos] Hide incoming file from home screen is saved

mobile/lib/services/filter/collection_ignore.dart

@@ -1,26 +1,38 @@
 import 'package:photos/models/file/file.dart';
 import "package:photos/services/filter/filter.dart";
 
-// CollectionsIgnoreFilter will filter out files that are in present in the
-// given collections. This is useful for filtering out files that are in archive
-// or hidden collections from home page and other places
-class CollectionsIgnoreFilter extends Filter {
+// CollectionsOrHashIgnoreFilter will filter out all files that are in present in the
+// given collections collectionIDs. This is useful for filtering out files that are in archive
+// or hidden collections from home page and other places. Based on flag, it will also filter out
+// shared files if the user already as another file with the same hash.
+class CollectionsAndSavedFileFilter extends Filter {
   final Set<int> collectionIDs;
+  final bool ignoreSavedFiles;
+  final int ownerID;
 
   Set<int>? _ignoredUploadIDs;
+  Set<String> ownedFileHashes = {};
 
-  CollectionsIgnoreFilter(this.collectionIDs, List<EnteFile> files) : super() {
+  CollectionsAndSavedFileFilter(
+    this.collectionIDs,
+    this.ownerID,
+    List<EnteFile> files,
+    this.ignoreSavedFiles,
+  ) : super() {
     init(files);
   }
 
   void init(List<EnteFile> files) {
     _ignoredUploadIDs = {};
-    if (collectionIDs.isEmpty) return;
     for (var file in files) {
-      if (file.collectionID != null &&
-          file.isUploaded &&
-          collectionIDs.contains(file.collectionID!)) {
-        _ignoredUploadIDs!.add(file.uploadedFileID!);
+      if (file.collectionID != null && file.isUploaded) {
+        if (collectionIDs.contains(file.collectionID!)) {
+          _ignoredUploadIDs!.add(file.uploadedFileID!);
+        } else if (ignoreSavedFiles &&
+            file.ownerID == ownerID &&
+            (file.hash ?? '').isNotEmpty) {
+          ownedFileHashes.add(file.hash!);
+        }
       }
     }
   }
@@ -37,6 +49,16 @@ class CollectionsIgnoreFilter extends Filter {
       }
       return true;
     }
-    return !_ignoredUploadIDs!.contains(file.uploadedFileID!);
+    if (_ignoredUploadIDs!.contains(file.uploadedFileID!)) {
+      return false; // this file should be filtered out
+    }
+    if (ignoreSavedFiles &&
+        file.ownerID != ownerID &&
+        (file.hash ?? '').isNotEmpty) {
+      // if the file is shared and the user already has a file with the same hash
+      // then filter it out by returning false
+      return !ownedFileHashes.contains(file.hash!);
+    }
+    return true;
   }
 }

mobile/lib/services/filter/db_filters.dart

@@ -1,3 +1,4 @@
+import "package:photos/core/configuration.dart";
 import 'package:photos/models/file/file.dart';
 import "package:photos/services/filter/collection_ignore.dart";
 import "package:photos/services/filter/dedupe_by_upload_id.dart";
@@ -12,11 +13,14 @@ class DBFilterOptions {
   Set<int>? ignoredCollectionIDs;
   bool dedupeUploadID;
   bool hideIgnoredForUpload;
+  // If true, shared files that are already saved in the users account will be ignored.
+  bool ignoreSavedFiles;
 
   DBFilterOptions({
     this.ignoredCollectionIDs,
     this.hideIgnoredForUpload = false,
     this.dedupeUploadID = true,
+    this.ignoreSavedFiles = false,
   });
 
   static DBFilterOptions dedupeOption = DBFilterOptions(
@@ -42,12 +46,18 @@ Future<List<EnteFile>> applyDBFilters(
   if (options.dedupeUploadID) {
     filters.add(DedupeUploadIDFilter());
   }
-  if (options.ignoredCollectionIDs != null &&
-      options.ignoredCollectionIDs!.isNotEmpty) {
-    final collectionIgnoreFilter =
-        CollectionsIgnoreFilter(options.ignoredCollectionIDs!, files);
+
+  if ((options.ignoredCollectionIDs ?? <int>{}).isNotEmpty ||
+      options.ignoreSavedFiles) {
+    final collectionIgnoreFilter = CollectionsAndSavedFileFilter(
+      options.ignoredCollectionIDs ?? <int>{},
+      Configuration.instance.getUserID() ?? 0,
+      files,
+      options.ignoreSavedFiles,
+    );
     filters.add(collectionIgnoreFilter);
   }
+
   final List<EnteFile> filterFiles = [];
   for (final file in files) {
     if (filters.every((f) => f.filter(file))) {

mobile/lib/ui/home/home_gallery_widget.dart

@@ -41,6 +41,7 @@ class HomeGalleryWidget extends StatelessWidget {
           hideIgnoredForUpload: true,
           dedupeUploadID: true,
           ignoredCollectionIDs: collectionsToHide,
+          ignoreSavedFiles: true,
         );
         if (hasSelectedAllForBackup) {
           result = await FilesDB.instance.getAllLocalAndUploadedFiles(